Rivet gun



FIG. 1 is a perspective elevational view of a rivet gun showing my newdesign;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof; and

FIG. 5 is a front elevational view thereof.

The ornamental design for a rivet gun, substantially as shown.